Cultured kidney marrow from nfe2^−/−zebrafish supports normal hematopoietic development. Unfractionated kidney marrow was isolated from Tg(cd41:egfp);nfe2^−/− mutant and wild-type siblings and was cultured in the presence of Tpo + Carp serum alone, or with the addition of Epo/Gcsf. After culture, the total number of colony-forming units (CFUs) (A) and GFP⁺ CFUs (B) were counted. There were no significant differences in either total number of cells (A) or cells expressing GFP (B) between wild-type and homozygous mutant fish, with or without the addition of Epo and Gcsf.